Save changes of parent /child sheet rows together by button click

Please let me know how can i update the changes made in Parent / Child view rows in to Database.

I have populated the hierarchy with a parent / Child combination without any issues. ( Using data Table method ). I would like to save the changes made in parent/Child sheets together by the way of button click event method.

Will you please help me how can i achieve this. It would be helpful if you explain me with a sample code in vb.net